Any discussion of the prior art throughout the specification should in no way be considered as an admission that such prior art is widely known or forms part of common general knowledge in the field.
Exposure to radiation can, in some cases, lead to radiation poisoning, which is a form of damage to biological tissue due to an increased exposure to a source of ionising radiation. Radiation poisoning is generally used to refer to the acute problems caused by a large dose of radiation over a short period of time, although this can occur with long term exposure to low level radiation. Many of the symptoms of radiation poisoning are due to the interference of ionising radiation with cell division.
Ionising radiation comprises highly-energetic particles or waves that can detach at least one electron from an atom or molecule, thereby ionising it. Ionising ability is a function of the energy of individual particles or waves, and not a function of their number. A large number of particles or waves will not, in the most common situations, cause ionisation if the individual particles or waves are insufficiently energetic.
Examples of ionising radiation are energetic beta particles, neutrons, and alpha particles. X-rays and gamma-rays will ionise almost any molecule or atom; far ultraviolet light will ionise many atoms and molecules; near ultraviolet and visible light are ionising to very few molecules; microwaves and radio waves are non-ionising forms of radiation.
The symptoms of radiation exposure may vary but can present with nausea and vomiting; diarrhea; skin burns (radiodermatitis); weakness; fatigue; loss of appetite; fainting; dehydration; inflammation (swelling, redness or tenderness) of tissues; bleeding from your nose, mouth, gums or rectum; low red blood cell count (anaemia) and hair loss. The signs and symptoms of radiation exposure depend on how much radiation has been received and which tissues are exposed. Exposure to a radioactive source is also used in the treatment of cancer. Such exposure can also cause temporary chronic radiation poisoning.
At present it is not possible to reverse the effects of radiation exposure. Anaesthetics and antiemetics are administered to counter the symptoms of exposure, together with antibiotics for countering secondary infections due to the resulting immune system deficiency. Blood transfusions may also be necessary if anaemia develops.
Drugs approved by the Food and Drug Administration (FDA) for treatment of radiation contamination from an industrial accident or a dirty bomb include Radiogardase, pentetate calcium trisodium (Ca-DTPA) and pentetate zinc trisodium (Zn-DTPA). Radiogardase, also known as insoluble Prussian Blue, may be used to treat people exposed to radiation containing harmful amounts of cesium-137 or thallium. Ca-DTPA and Zn-DTPA may be used for contamination with radioactive forms of plutonium, americium and curium. All three drugs work to eliminate radioactive substances from the human body.
Another drug that may be helpful in cases of exposure to high doses of radiation is filgrastim (Neupogen), a drug currently used in people who have received chemotherapy or radiation therapy. This drug stimulates the growth of white blood cells and can help repair bone marrow damage.
It is an object of the present invention to overcome or ameliorate at least some of the deficiencies of the prior art or to provide a useful alternative.